bikini

noun

bi·​ki·​ni bə-ˈkē-nē 

plural bikinis

1

a

: a two-piece bathing suit worn by women that does not cover the midriff see also string bikini, tankini

b

: a short snug swimsuit worn by men

2

: a pair of low-cut briefs (see brief entry 2 sense 4)

Launched in May, the underwear brand for men and women includes bikinis, … G-strings and boxer briefs.

—Phyllis Furman

… ultra low-rise jeans with a built-in bikini or thong.

—Sunday Tribune (South Africa)

—often used before another noun

Bikini briefs are usually lower than the true waist, often at the hips.

—Clifford Pugh

bikinied adjective

or less commonly bikini'd

bə-ˈkē-nēd 

Did you know?

In July 1946, a US Army–Navy task force detonated two thermonuclear bombs at Bikini, an atoll in the Marshall Islands in the Pacific Ocean, and the event dominated news around the world. A French designer, Jacques Heim, used the occasion to introduce a skimpy two-piece bathing suit dubbed l’atome, “the atom.” Another designer, Louis Réard, followed it up with an even smaller suit for which he registered the name bikini. It was first modeled by dancer Micheline Bernardini at a Paris fashion show on July 5. There is no solid evidence for why he gave this name to the suit, but it has since become an international word.

Examples of bikini in a Sentence

Recent Examples on the Web

Other photos in the carousel showed Kourtney sunbathing in a black bikini, dinner dates, and sweet selfies, along with some special moments between her and little Rocky at Disneyland. —Clare Fisher, PEOPLE, 21 Apr. 2026

The new collection includes solid-colored one-pieces, as well as a colorful array of triangular bikini tops or Brazilian-cut briefs, tied at the sides to show even more skin. —Christian Allaire, Vogue, 21 Apr. 2026

For the special occasion, the mom-of-one wore a sheer T-shirt layered over a cheeky thong bikini by Rogue Season. —Emma Banks, InStyle, 13 Apr. 2026

Alamo seems to be warming up to her until one of the girls, the one whose bikini strings Rue tied, overdoses from Laurie’s drugs, which were laced with fentanyl. —Rafaela Bassili, Vulture, 13 Apr. 2026

Word History

Etymology

French, from Bikini, atoll of the Marshall Islands

First Known Use

1947, in the meaning defined at sense 1a

Phrases Containing bikini

• bikini wax
• string bikini

Rhymes for bikini

• acini
• aldine
• arsine
• carinii
• cosine
• delphine
• domine
• latine
• leucine
• ovine
• pennine
• porcine

Kids Definition

bikini

noun

bi·​ki·​ni bə-ˈkē-nē 

: a scanty two-piece bathing suit for a girl or woman

Etymology

from French bikini "two-piece bathing suit," from Bikini, atoll in the Marshall Islands

Geographical Definition

Bikini

geographical name

Bi·​ki·​ni bi-ˈkē-nē 

island (atoll) of the Marshall Islands

Note: Bikini was the site of U.S. atomic bomb tests in 1946 and hydrogen bomb tests in 1954 and 1956.

Bikinian

bi-ˈkē-nē-ən 

noun